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Full text of "The manufacture and properties of iron and steel"

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508                                    THE IRON INDUSTRY.
If we add 60 cents for labor and 25 cents for supplies, which are figures given by Earchhoff, we have a total of $7.35 for the best managed and equipped plants owning their coal and ore mines, and $9.40 for plants buying their raw material and using more fuel. Some works show a higher cost. These totals do not include general expenses and administration, nor the interest and deprecia-tion account, so that they, by no means represent the cost of pig-iron in Cleveland. They may, however, be compared with similar calculations where the cost of pig-iron in different localities is confidently predicted, as in such cases these latter items are always ignored. It may be pertinent to record that the selling price of Cleveland iron in 1900-01 was $11.20 per ton. '
Thus Cleveland iron can be made cheaply, but it is an undesirable metal. It contains so much phosphorus that it is hard to use in a basic open-hearth furnace, although it is certain that it can be so used. On the other hand, it contains so little phosphorus that it is not well fitted for the basic Bessemer. For the basic converter it has been customary to enrich the phosphorus content by adding puddle cinder, and to raise the manganese by manganiferous imported ores. With the diminution of the supply of puddle cinder it is necessary to use basic converter slag in the blast furnaces, and no matter what the mixture may be, the silicon must be kept low, thus requiring a large amount of lime to flux the high silica in the ore. Taking everything together, the cost of making iron for the basic converter is given by Kirchhoff at from $1 to $1.50 pear ton above the ordinary product, For open-hearth work the manganese is not necessary and the phosphorus an injury. It would seem, therefore, as if a cheap iron could be made for this purpose, while the phosphorus might be lessened by mixing with foreign ores.
The price of Spanish ore in the winter of 1900-01 was about $2.61 at Bilbao, with the low ocean freight of $1.03, making a total of $3.64 per ton at Middlesbrough. As the ore contains about 49 per cent, of iron, this gives 7.43 cents per unit, or about $7.06 per ton of iron. The assumption that the ore contains only 49 per cent, of iron may seem pessimistic, but the decrease in the quality of the Spanish ores has been a serious matter. This subject was discussed in the presidential address of William Whitwell before the Iron and Steel Institute, and he gave the composition of Rubio